/*

   Derby - Class org.apache.derby.impl.jdbc.EmbedDatabaseMetaData40

   Licensed to the Apache Software Foundation (ASF) under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for additional information regarding copyright ownership.
   The ASF licenses this file to you under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

 */

package org.apache.derby.impl.jdbc;

import java.sql.RowIdLifetime;
import java.sql.SQLException;
import org.apache.derby.iapi.reference.SQLState;

public class EmbedDatabaseMetaData40 extends EmbedDatabaseMetaData {
    
    public EmbedDatabaseMetaData40(EmbedConnection connection, String url) throws SQLException {
        super(connection,url);
    }

    /**
     * Retrieves the major JDBC version number for this driver.
     *
     * @return JDBC version major number
     */
    public int getJDBCMajorVersion() {
        return 4;
    }

    /**
     * Retrieves the minor JDBC version number for this driver.
     *
     * @return JDBC version minor number
     */
    public int getJDBCMinorVersion() {
        return 0;
    }

    public RowIdLifetime getRowIdLifetime() throws SQLException {
        return RowIdLifetime.ROWID_UNSUPPORTED;
    }

    public boolean supportsStoredFunctionsUsingCallSyntax() throws SQLException {
        return true;
    }

    /**
     * Returns whether or not all open {@code ResultSet}s on a {@code
     * Connection} are closed if an error occurs when auto-commit in enabled.
     *
     * @return {@code true}, since the embedded driver will close the open
     * {@code ResultSet}s
     */
    public boolean autoCommitFailureClosesAllResultSets() throws SQLException {
        return true;
    }

    /**
     * Returns false unless <code>interfaces</code> is implemented 
     * 
     * @param  interfaces             a Class defining an interface.
     * @return true                   if this implements the interface or 
     *                                directly or indirectly wraps an object 
     *                                that does.
     * @throws java.sql.SQLException  if an error occurs while determining 
     *                                whether this is a wrapper for an object 
     *                                with the given interface.
     */
    public boolean isWrapperFor(Class<?> interfaces) throws SQLException {
        return interfaces.isInstance(this);
    }
    
    /**
     * Returns <code>this</code> if this class implements the interface
     *
     * @param  interfaces a Class defining an interface
     * @return an object that implements the interface
     * @throws java.sql.SQLExption if no object if found that implements the 
     * interface
     */
    public <T> T unwrap(java.lang.Class<T> interfaces) 
                            throws SQLException{
        //Derby does not implement non-standard methods on 
        //JDBC objects
        //hence return this if this class implements the interface 
        //or throw an SQLException
        try {
            return interfaces.cast(this);
        } catch (ClassCastException cce) {
            throw newSQLException(SQLState.UNABLE_TO_UNWRAP,interfaces);
        }
    }

}
